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Quote:

Originally Posted by blue thunder (Post 2395163)

Sshh, don't tell raddiction that, I can't have him rompin past me laughing his ars off :angry-smiley-038:

My setup is similar to yours NW but my cid is 470. Rect port heads, dart sp intakes last year with 800dp. Runs pretty strong and I have been happy with them. Couple years back I ran same edelbrock alum rect port heads with dp performer intakes. She ran better then. I actually lost 2mph going with the single plane. Now I am going with small blowers and dominator carbs. If I go back to n/a it would be with the dp peformer intakes. I have 2 blue hp 500 takeoff carbs to sell (800dp) if you are interested. I would definately dump the qjets and I have spent a lot time an money trying to make they work, they just can't match the holley.

Based on your rpm goal, single plane is a no brainer and I think the dominators a good starting point.

BT :cool-smiley-011:

BT -
Agreed about the Q-Jets and Holleys, but $$ are tight and I have other priorities right now. (However, if you're only looking for a wink and a slap on the a$$, PM me). Take a look at what I started with...
What cam are you running? I'm probaby blowing bubbles thinking I can have both ends of the spectrum with the rect heads, but I have my eye set on the CC XM284HR as soon as I can afford the $2k upgrade.
I have the original 454 7.4l GM cams and a couple of CC 286H I want to check out.The 286, although flat tappet, will give me an idea of the trade-off between bottom end torque and WOT with the rect heads.
My blocks are with Active Performance for machining now..I plan on some lightweight 9.5:1 domes with H-Beams so I'm hoping the increased compression will overcome some of the low end "bog".:boat:

I run the comp cams cb xm 278h-12 cams. Flat tappet you know. Approx 9.5:1 compression. They run real strong up to 5400 or so. Bravo drives won't last going too high rpm wise. You should consider that NW.

Where you at Raddiction?

Quote:

Originally Posted by blue thunder (Post 2395552)

The recommendation on the Bravo Drives is the best bit of info on this thread. Watch your Torque and RPM. As for the heads, AFR for sure if you can afford them. Matched with a good intake and custom cam. A custom cam is NOT that much more then what you can purchase from Summit. Dump the Qjets and pick a good mechanical 4150 Holley HP. Now if the AFR's are out of price range, the Edelbrock large oval marine heads are a good second choice. Yeah, 1540.00 does not include the guides, springs, etc. But you can complete them with YOUR choice of products and be under 2K. Not bad for alum large ovals.

I have done something very close to this motor project, made 550HP/600TQ at 5400 with less CI and a stinking Air Gap dual plane intake. Did not spend a bundle getting it either.

Second best recommendation (IMHO):
Custom CAM by RMbuilder
Carb calibrated by Nickerson

Quote:

Originally Posted by Chris Sunkin (Post 2395197)

Aren't the Edelbrock marine heads about that same price? They seem like a deal for an assembled aluminum head with inconel valves- what's the catch?

Other than the weight I think the Dart's make more power.

Quote:

Originally Posted by TylerCrockett (Post 2395711)

Other than the weight I think the Dart's make more power.

Agreed

Thanks for the info guys......keep it comin'!!:D:cool-smiley-011:

Quote:

Originally Posted by TylerCrockett (Post 2395711)

Other than the weight I think the Dart's make more power.

Hey Tyler, do you mean these heads?
http://www.sonnysracing.com/products...portheads.html

Ok, fun stuff put aside, you and Mr. Gellner have tons of experience in the marine performance arena. How would you score a Dart Iron Eagle vs. an AFR counterpart? I.E. similar runner and cc volume.

Good question Rotax.....Dean/Tyler what are your thoughts.:cool-smiley-011:

Heres a little more to think about.....

Can the 502 MAG/MPI injection setup support the HP I'm looking for?

R Addiction, there is a local guy in Thordale, Pa. that could hook you up with some BAD heads. I hear he does some BAD work!!:cool-smiley-027: